new bmesh queries BM_face_exists_overlap, BM_face_exists_overlap_subset

the subset version of the function checks if any faces has all its verts in the given array.

also made some additions to linklist functions (arena and pool versions of append).

4 files changed, 173 insertions, 16 deletions

diff --git a/source/blender/blenlib/BLI_linklist.h b/source/blender/blenlib/BLI_linklist.h
index 9c1e1f88bab..2ca363ee780 100644
--- a/source/blender/blenlib/BLI_linklist.h
+++ b/source/blender/blenlib/BLI_linklist.h
@@ -54,10 +54,16 @@ struct LinkNode *BLI_linklist_find(struct LinkNode *list, int index);
 
 void    BLI_linklist_reverse(struct LinkNode **listp);
 
+void    BLI_linklist_prepend_nlink(struct LinkNode **listp, void *ptr, struct LinkNode *nlink);
 void    BLI_linklist_prepend(struct LinkNode **listp, void *ptr);
-void    BLI_linklist_append(struct LinkNode **listp, void *ptr);
 void    BLI_linklist_prepend_arena(struct LinkNode **listp, void *ptr, struct MemArena *ma);
 void    BLI_linklist_prepend_pool(struct LinkNode **listp, void *ptr, struct BLI_mempool *mempool);
+
+void    BLI_linklist_append_nlink(LinkNode **listp, void *ptr, LinkNode *nlink);
+void    BLI_linklist_append(struct LinkNode **listp, void *ptr);
+void    BLI_linklist_append_arena(LinkNode **listp, void *ptr, struct MemArena *ma);
+void    BLI_linklist_append_pool(LinkNode **listp, void *ptr, struct BLI_mempool *mempool);
+
 void   *BLI_linklist_pop(struct LinkNode **listp);
 void   *BLI_linklist_pop_pool(struct LinkNode **listp, struct BLI_mempool *mempool);
 void    BLI_linklist_insert_after(struct LinkNode **listp, void *ptr);
@@ -67,4 +73,7 @@ void    BLI_linklist_freeN(struct LinkNode *list);
 void    BLI_linklist_free_pool(LinkNode *list, LinkNodeFreeFP freefunc, struct BLI_mempool *mempool);
 void    BLI_linklist_apply(struct LinkNode *list, LinkNodeApplyFP applyfunc, void *userdata);
 
-#endif
+#define BLI_linklist_prepend_alloca(listp, ptr) \
+	BLI_linklist_prepend_nlink(listp, ptr, alloca(sizeof(LinkNode)))
+
+#endif  /* __BLI_LINKLIST_H__ */
diff --git a/source/blender/blenlib/intern/BLI_linklist.c b/source/blender/blenlib/intern/BLI_linklist.c
index 99fc5f27726..66fcfd21fbb 100644
--- a/source/blender/blenlib/intern/BLI_linklist.c
+++ b/source/blender/blenlib/intern/BLI_linklist.c
@@ -89,18 +89,39 @@ void BLI_linklist_reverse(LinkNode **listp)
 	*listp = rhead;
 }
 
-void BLI_linklist_prepend(LinkNode **listp, void *ptr)
+/**
+ * A version of prepend that takes the allocated link.
+ */
+void BLI_linklist_prepend_nlink(LinkNode **listp, void *ptr, LinkNode *nlink)
 {
-	LinkNode *nlink = MEM_mallocN(sizeof(*nlink), "nlink");
 	nlink->link = ptr;
-	
 	nlink->next = *listp;
 	*listp = nlink;
 }
 
-void BLI_linklist_append(LinkNode **listp, void *ptr)
+void BLI_linklist_prepend(LinkNode **listp, void *ptr)
 {
 	LinkNode *nlink = MEM_mallocN(sizeof(*nlink), "nlink");
+	BLI_linklist_prepend_nlink(listp, ptr, nlink);
+}
+
+void BLI_linklist_prepend_arena(LinkNode **listp, void *ptr, MemArena *ma)
+{
+	LinkNode *nlink = BLI_memarena_alloc(ma, sizeof(*nlink));
+	BLI_linklist_prepend_nlink(listp, ptr, nlink);
+}
+
+void BLI_linklist_prepend_pool(LinkNode **listp, void *ptr, BLI_mempool *mempool)
+{
+	LinkNode *nlink = BLI_mempool_alloc(mempool);
+	BLI_linklist_prepend_nlink(listp, ptr, nlink);
+}
+
+/**
+ * A version of append that takes the allocated link.
+ */
+void BLI_linklist_append_nlink(LinkNode **listp, void *ptr, LinkNode *nlink)
+{
 	LinkNode *node = *listp;
 	
 	nlink->link = ptr;
@@ -117,22 +138,22 @@ void BLI_linklist_append(LinkNode **listp, void *ptr)
 	}
 }
 
-void BLI_linklist_prepend_arena(LinkNode **listp, void *ptr, MemArena *ma)
+void BLI_linklist_append(LinkNode **listp, void *ptr)
+{
+	LinkNode *nlink = MEM_mallocN(sizeof(*nlink), "nlink");
+	BLI_linklist_append_nlink(listp, ptr, nlink);
+}
+
+void BLI_linklist_append_arena(LinkNode **listp, void *ptr, MemArena *ma)
 {
 	LinkNode *nlink = BLI_memarena_alloc(ma, sizeof(*nlink));
-	nlink->link = ptr;
-	
-	nlink->next = *listp;
-	*listp = nlink;
+	BLI_linklist_append_nlink(listp, ptr, nlink);
 }
 
-void BLI_linklist_prepend_pool(LinkNode **listp, void *ptr, BLI_mempool *mempool)
+void BLI_linklist_append_pool(LinkNode **listp, void *ptr, BLI_mempool *mempool)
 {
 	LinkNode *nlink = BLI_mempool_alloc(mempool);
-	nlink->link = ptr;
-
-	nlink->next = *listp;
-	*listp = nlink;
+	BLI_linklist_append_nlink(listp, ptr, nlink);
 }
 
 void *BLI_linklist_pop(struct LinkNode **listp)
diff --git a/source/blender/bmesh/intern/bmesh_queries.c b/source/blender/bmesh/intern/bmesh_queries.c
index 6eab3c625fa..ddc8f371501 100644
--- a/source/blender/bmesh/intern/bmesh_queries.c
+++ b/source/blender/bmesh/intern/bmesh_queries.c
@@ -35,6 +35,7 @@
 
 #include "BLI_math.h"
 #include "BLI_alloca.h"
+#include "BLI_linklist.h"
 
 #include "bmesh.h"
 #include "intern/bmesh_private.h"
@@ -1684,6 +1685,129 @@ bool BM_face_exists_multi_edge(BMEdge **earr, int len)
 	return ok;
 }
 
+
+/**
+ * Given a set of vertices (varr), find out if
+ * all those vertices overlap an existing face.
+ *
+ * \return Success
+ *
+ * \param varr  Array of unordered verts.
+ * \param len  \a varr array length.
+ * \param r_f_overlap  The overlapping face to return.
+ */
+
+bool BM_face_exists_overlap(BMVert **varr, const int len, BMFace **r_f_overlap)
+{
+	BMIter viter;
+	BMFace *f;
+	int i;
+	bool is_overlap = false;
+	LinkNode *f_lnk = NULL;
+
+	if (r_f_overlap) {
+		*r_f_overlap = NULL;
+	}
+
+#ifdef DEBUG
+	/* check flag isn't already set */
+	for(i = 0; i < len; i++) {
+		BM_ITER_ELEM (f, &viter, varr[i], BM_FACES_OF_VERT) {
+			BLI_assert(BM_ELEM_API_FLAG_TEST(f, _FLAG_OVERLAP) == 0);
+		}
+	}
+#endif
+
+	for(i = 0; i < len; i++) {
+		BM_ITER_ELEM (f, &viter, varr[i], BM_FACES_OF_VERT) {
+			if (BM_ELEM_API_FLAG_TEST(f, _FLAG_OVERLAP) == 0) {
+				if (len <= BM_verts_in_face(f, varr, len)) {
+					if (r_f_overlap)
+						*r_f_overlap = f;
+
+					is_overlap = true;
+					break;
+				}
+
+				BM_ELEM_API_FLAG_ENABLE(f, _FLAG_OVERLAP);
+				BLI_linklist_prepend_alloca(&f_lnk, f);
+			}
+		}
+	}
+
+	for (; f_lnk; f_lnk = f_lnk->next) {
+		BM_ELEM_API_FLAG_DISABLE((BMFace *)f_lnk->link, _FLAG_OVERLAP);
+	}
+
+	return is_overlap;
+}
+
+/**
+ * Given a set of vertices (varr), find out if
+ * there is a face that uses vertices only from this list
+ * (that the face is a subset or made from the vertices given).
+ *
+ * \param varr  Array of unordered verts.
+ * \param len  varr array length.
+ */
+bool BM_face_exists_overlap_subset(BMVert **varr, const int len)
+{
+	BMIter viter;
+	BMFace *f;
+	int i;
+	bool is_overlap = false;
+	LinkNode *f_lnk = NULL;
+
+#ifdef DEBUG
+	/* check flag isn't already set */
+	for(i = 0; i < len; i++) {
+		BLI_assert(BM_ELEM_API_FLAG_TEST(varr[i], _FLAG_OVERLAP) == 0);
+		BM_ITER_ELEM (f, &viter, varr[i], BM_FACES_OF_VERT) {
+			BLI_assert(BM_ELEM_API_FLAG_TEST(f, _FLAG_OVERLAP) == 0);
+		}
+	}
+#endif
+
+	for(i = 0; i < len; i++) {
+		BM_ELEM_API_FLAG_ENABLE(varr[i], _FLAG_OVERLAP);
+	}
+
+	for(i = 0; i < len; i++) {
+		BM_ITER_ELEM (f, &viter, varr[i], BM_FACES_OF_VERT) {
+			if (BM_ELEM_API_FLAG_TEST(f, _FLAG_OVERLAP) == 0) {
+				/* check if all vers in this face are flagged*/
+				BMLoop *l_iter, *l_first;
+				l_iter = l_first = BM_FACE_FIRST_LOOP(f);
+				is_overlap = true;
+				do {
+					if (BM_ELEM_API_FLAG_TEST(l_iter->v, _FLAG_OVERLAP) == 0) {
+						is_overlap = false;
+						break;
+					}
+				} while ((l_iter = l_iter->next) != l_first);
+
+				if (is_overlap) {
+					break;
+				}
+
+				BM_ELEM_API_FLAG_ENABLE(f, _FLAG_OVERLAP);
+				BLI_linklist_prepend_alloca(&f_lnk, f);
+			}
+		}
+	}
+
+	for(i = 0; i < len; i++) {
+		BM_ELEM_API_FLAG_DISABLE(varr[i], _FLAG_OVERLAP);
+	}
+
+	for (; f_lnk; f_lnk = f_lnk->next) {
+		BM_ELEM_API_FLAG_DISABLE((BMFace *)f_lnk->link, _FLAG_OVERLAP);
+	}
+
+	return is_overlap;
+}
+
+
 /* convenience functions for checking flags */
 bool BM_edge_is_any_vert_flag_test(const BMEdge *e, const char hflag)
 {
diff --git a/source/blender/bmesh/intern/bmesh_queries.h b/source/blender/bmesh/intern/bmesh_queries.h
index 2c931de995e..38d30b2d005 100644
--- a/source/blender/bmesh/intern/bmesh_queries.h
+++ b/source/blender/bmesh/intern/bmesh_queries.h
@@ -95,6 +95,9 @@ bool    BM_face_exists(BMVert **varr, int len, BMFace **r_existface);
 bool    BM_face_exists_multi(BMVert **varr, BMEdge **earr, int len);
 bool    BM_face_exists_multi_edge(BMEdge **earr, int len);
 
+bool    BM_face_exists_overlap(BMVert **varr, const int len, BMFace **r_f_overlap);
+bool    BM_face_exists_overlap_subset(BMVert **varr, const int len);
+
 int     BM_face_share_face_count(BMFace *f_a, BMFace *f_b);
 int     BM_face_share_edge_count(BMFace *f1, BMFace *f2);